Apparatus for automatically controlling gas pressure on beverages



June l, 1943. w. R. KRoMl-:R ErAL 2,320,969

APPARATUS FOR AUTOMATICALLY CONTROLLING GAS PRESSURE ON BEVERGES Filed NOV. 13, 1940 2 Sheets-Sheet l .11441155 Illlfflllfrl'lill'IlIliffflllillllfllllllllll INVENTORS Wallace R. Kramer Harvgf E Elliott BY v le ATroRNEYs June l 1943 w. R. KROMl-:R ETAL 2,320,969

APPARATUS FOR AUTOMTICALLY CONTROLLING GAS PRESSURE ON BEVERAGES Filed Nov. 15, 1940 2 sheets-sheet 2 Yil awel/gwa ff INVENToRs Wllace R. Kramer Harvely E Elliott Patented June 1, 1943 APPARATUS FOR AUTOMATICALLY CON- TROLLING GAS PRESSURE ON BEVERAGES Wallace R. Kromer and Harvey F. Elliott, Cleveland, Ohio,

assignors to The Kromer-Niernan Company, Cleveland, Ohio, a corporation of Ohio Application November 13, 1940, Serial No. 365,480

8 Claims.

This invention relates to an improved method of and apparatus or equipment for storing and dispensing beverages, and more particularly to an improved method and apparatus for controlling the supply of gas to a dispenser or storage receptacle for beer and the like.

Carbonated beverages, particularly beer and ale which have a quantity of carbon dioxide formed during their manufacture, are necessarily kept under pressure in order to avoid loss of the desirable carbon dioxide content. In the handling and dispensing of beverages such as beer and ale, a gas pressure is maintained in the storage or dispensing receptacle by means of a pump, supply tank or other source of gas under pressure. The receptacle or container is usually in the form of a keg or barrel and authorities differ as to the type of gas preferred to maintain pressure on the beverage. Some prefer to introduce carbon dioxide into the receptacle or keg so that. the pressure is maintained on the beverage by the same kind of gas as that with which the beverage is charged. Others prefer to maintain the pressure on the beverage in the keg or receptacle by the introduction of air, as by a pump.

The exact quantity of carbon dioxide that is dissolved in the brewed beverage is considered by many to be critical, or at least to be influential on the quality and palatability of the beverage, Therefore, and in order to serve beer and ale having a uniform quality and taste, brewers and retailers are anxious to maintain the carbon dioxide content of their beverage constant and the same as that present in the beer as manufactured at the brewery. There are, however, many variables which influence the carbon dioxide content of the beer as it is served. For example, one of the chief factors inuencing the carbon dioxide content of draft beer is the temp erature at which the the keg or other storage receptacle from which it is to be grawn from time to time as desired. At elevate temperatures the solubility of the carbon dioxide in the beverage is decreased and the gas tends to escape from the beverage, usually resulting in an increased pressure within the keg or other storage receptacle. At low temperatures the solubility of carbon dioxide is increased and tends to dissolve in the beverage. As is well known, there is a dente relationship between the pressure of carbon dioxide gas maintained in contact with a quantity of beer, the, temperature of the beer and the gas, and the quantity of gas that is dissolved in the beer. A change in any beverage is maintained in one of these factors changes at least one or the other. This relationship between pressure temperature and dissolved content of carbon dioxide is frequently graphically set forth in what is known as a pressure temperature curve. That is to say, if it is desirable to maintain in the beer a carbon dioxide content equivalent to 21/2 times the volume of the beverage, then for every temperature to which the beverage is subjected. there is a corresponding pressure of carbon dioxide gas that must be maintained on the beverage, If such pressure drops without a change in temperature, carbon dioxide escapes from the beverage; while if such pressure increases without a change in temperature, carbon dioxide is absorbed or dissolved by the beer.

It is customary in the present handling of draft beer and ale to maintain a predetermined carbon dioxide or other gas pressure in the kegs or receptacles storing the beverage by means of a pressure regulating valve which receives the gas from a suitable source under a relatively high pressure and throttles the gas to the desired pressure to be` maintained on the beverage in the receptacle. During the withdrawal of beverage from the receptacle or keg for consumpu tion, an equivalent quantity of gas or carbon dioxide is automatically admitted to the receptacle by the regulating valve under the predetermined pressure so that there is normally no appreciable change in the pressure within the keg and the volumetric content of carbon dioxide in the stored beverage remains substantially constant. Operating in this manner is satisfactory so long as the temperature of the keg or other receptacle and the contained beverage is maintained constant. If, however, circumstances require that the receptacle or kegs on tap be placed in a room of varying temperature, the ordinary pressure regulating valve is ineffective to maintain a constant volumetric relationship between the beverage and the dissolved carbon dioxide. For example, if the pressure regulator is set tovmaintain 15 lbs. pressure on the beverage in the storage receptacle and' at this pressure the correct amount of carbon dioxide is maintained dissolved in the beverage at about 40 F., then upon anincrease in temperature o f the receptacle and its contents some carbon dioxide will escape from the beverage, while at each lowering of the temperature of the receptacle and its contents some additional carbon dioxide will be absorbed by the beer. A

It is, therefore, the principal object of the present invention to provide a generally improved Ate!!! method of and apparatus for handling and dispensing beverage wherein a predetermined volumetric relationship can be automatically maintained between the beverage and the dissolved carbon dioxide.

Another obiect is to provide an apparatus ior supplying gas under pressure to stored beverage and for automatically supplying the gas at increased pressure in response to an increase in ture of the beverage.

Another object is to provide an apparatus for supplying gas under pressure to stored beverage and for automatically decreasing thepressure of the supplied gas in response to a decrease in temperature of such beverage.

Another object is to provide apparatus for sup- Dlyins gas under pressure to a quantity of beverage and for automatically maintaining a predetermined relationship between the pressure of the gas supplied and the temperature of such beverage. to increase the pressure of supplied gas in proportion to temperature increases in the beverage. and also to decrease the pressure of gas supplied to the beverage proportionately to temperature decreases of the beverage.

Another object is to provide an improved method of and apparatus for controlling the operation of a pressure regulating valve for use in association with a beverage dispensing system so as to increase and decrease the pressure of the gas delivered by the valve in proportion to temperature changes o! the beverage stored in the system.

Another object is to provide a pressure regulating valve and a control therefor associated with a tap rod for use in withdrawing beverage from a keg or barrel so that temperature changes in the beverage which iniiuence the tap rod are utilized by the latter in governing the pressure regulating valve.

Another object o! the invention is to provide, in association with a pressure regulating valve, temperature responsive means for governing the valve, the temperature responsive means being associated with the tap rod of a keg or barrel of a conventional beverage dispensing system. More speciiically, the proved combination tap rod and pressure regulating valve. The invention also aims to provide an improved pressure regulating valve which is motivated and which is governed by thermal responsive fluid inuenced by the temperature of a metallic tap rod extending into the beverage in a receptacle or keg.

Another object is to provide a generally improved apparatus ior' controlling the pressure on beverage which is simple in design and construction and relatively inexpensive to manufacture. Other objects and advantages will become apparent from the following detailed description oi suitable embodiments of the invention made in connection with the accompanying drawings, in which:

Figure 1 is an elevational view partly in section showing a portion of the equipment used in a beer dispensing system and embodying the present invention; Y

Fig. 2 is an elevational view, mainly in section, showing. the tap rod and the regulating valve of the apparatus shown in Fig. land enlarged with respect thereto:

Fig.'3 is an elevational view partly in section showing a modincation oi an invention;

Fig. 4 is an elevational view with parts removed showing the regulating valve and the control and the drive therefor of Fig. 3;

invention aims to provide an im Fig. 5 is a sectional detail with parts broken broken away of the drive and the control apparatus shown in Fig. 4; and

Fig. 6 is a wiring diagram showing the electrical connections for the drive and the control illustrated in Figs. 3 through 5.

Referring now to the drawings by reference numerals which indicate like parts throughout the several views, the invention is shown incorporated in beverage dispensing systems of the type in which the beer or other beverage is received in kegs or barrels and in which it is kept until withdrawn to be cooled and dispensed to the consumer. The apparatus for cooling the beverage and the faucet or faucets through which it is dispensed are not shown since these parts are conventional and the present invention relates particularly to the maintenance of a certain pressure or pressures on the beverage in the storage receptacle or container. In Fig. 1 this receptacle or container is in the form of a keg or hall barrel indicated at K, and a tap rod T extends into the keg so that beverage can be withdrawn as desired. Supported on the tap rod T is a. pressure regulating valve V which receives gas under pressure from a suitable source of supply such as a tank of compressed carbon dioxide indicated at S.

A suitable flexible conduit I connects the gas source S to the valve V and a stopcock or shut-oir 2 may be provided in the usual manner. The valve V is supported on the tap rod T and the latter is received in a fitting F of conventional construction which eiects a fluid-tight connection with the keg or receptacle K. A ilexible conduit 3 extends between the regulating valve V and the fitting F to carry gas from the valve to the keg. If desired, a suitable shut-ofi valve 4 may be provided on the iltting F to close the connection of the fitting to the conduit 3. Beverage is conducted from the tap rod T to the cooling and dispensing equipment of the system through the beer line or conduit 5 which, if desired, may be provided with a stop valve 6.

As shown in Fig. 1, the tap rod T extends so that the bottom end 1 thereof is adjacent the bottom of the key K. Thus, a large portion of the tap rod is immersed in the beverage contained in the keg or receptacle and is in heat exchanging relation therewith. The tap rod T is of composite construction, having an outer tube 8 and an inner tube 9. These tubes may be of circular section and are telescopically arranged. Preierably the inner tube 9 is spaced from the outer tube to provide a circumferentially extending clearance lil. Materials having different coefficients oi thermal expansion are used for the tubes l and 8 so that upon a change in temperature of the tubes one will expand or contract relative to the other. Preferably both the inner and outer tubes of the tap rod are of metal to obtain certain heat conduction characteristics, as well as to secure adequate strength. Various metals can be used for the tubes, such, for example, as Invar or nickel steel for the outer tube 8 and copper or brass for the inner tube l. Preferably, the tubes are coated or plated with a suitable neutral metal or material, such as by being tinned, as is customary in beer dispensing equipment, for the purpose ot avoiding reaction with the beer or other beverage. At the lower or bottom end 1 of the tap rod T the tubes l and 8 are secured together. as by welding or soldering, indicated at I I. Thus, upon an increase in temperature of the tubes, the inner tube expands more than the outer tube and upwardly and longitudinally with respect to upper end I5 of the outer tube 8. Upon a decrease in the temperature of the tap rod, the end I4 of the inner tube moves downwardly with respect to the upper end I5 of the outer tube 8.

Beverage enters passageway I5 of the inner tube 9 at the bottom end 1 of the tap rod and flows out of the passageway I5 through a lateral extension conduit I1 which is secured to the inner tube 9 of the tap rod and extends through an enlarged or elongated opening I8 in the outer tube 8 adjacent the upper end I5 of the latter. If desired, a split spacer or guide sleeve I9 may be provided to embrace thev inner tube 9 and the extension I1 of the latter adjacent the opening I8 in the outer tube. 'I'he split sleeve I9, which may be made of fiber or similar material, thus lills the space I and prevents entrance of foreign material into the latter through the opening I8 as well as guiding the inner tube 9 to maintain the latter centered with the outer tube 8. During expansion and contraction of the inner tube 9 relative to the outer tube 8, the sleeve |9 may slide longitudinally in the outer tube and is suiiioiently longer than the elongated opening I8 to maintain the latter closed to the space Il) in all normal positions.

A threaded collar 20 is secured on the upper end I of the outer tube 8, as by solder, and threadedly receives bottom casing portion 2| of the regulator valve V. Upper casing portion 22 of the valve is threaded into the lower casing portion 2|, as indicated at 23, and a exible diaphragm 24 is engaged between the valve casing portions 2| and 22 to divide the internal compartment of the valve into upper and lower chambers 25 and 25, respectively. A vent hole 38 in the lower casing portion maintains atmospheric pressure in the chamber 25.

Carbon dioxide or other suitable gas enters the valve V from the gas source through the stoppassage 28 into a high pressure chamber 29 formed in the upper casing part 22. A passage 30 extending between the high pressure chamber 29 and the controlled pressure chamber 25 is normally provided with a poppet type valve 3| having disc 32 and a stem guided by a spider 33. The valve 3| is urged toward or against seat 34 by a helical compression spring 35 which extends through the chamber 29 and seats on a retainer 39 which bearsagainst an adjustable screw 51 threadedly carried by a sleeve or bushing 36. This bushing is threaded at 31 into the casing pari; 22 and is provided with a sealing cap 58 threaded into one end of the bushing over the adjusting screw 51.

A bolt 4I) extends through a hole in the center of the diaphragm 24 and is threaded into a pressure member or plate 4I which bears against the underside of' the diaphragm. A helical compression spring 42, stronger than the spring 35, ex-

ends between the ing member or retainer 43 carried by a spindle 44 connected to the upper end of the tube 9. The spindle 44 may be provided with a pointed end 45 which is received within a tapered socket 45 formed in the underside of the retainer 43. If desired, the lower end of the spindle 44 may be received within the upper end of the inner tube 9 to provide a plug for the latter, preventing the escape of beverage therefrom. An integral collar 41 on the spindle 44 seats against the upper end ot the inner tube 9 and the spindle is guided in pressure plate 4I and a bearan opening formed in the lower casing part 2|, to be held thereby in line with the stem oi the valve 3|.

In assembling the pressure regulating valve V the parts are adjusted so that the spring 42 supported by the member 43 carried on the spindle 44 forces the bolt 48 against end 48 of the stem of the valve 3| so that the latter is unseated against the pressure of the spring 35 and high pressure gas from the chamber 29 ilows through the passage 39 into the chamber 25. Gas under pressure in the chamber 25 acts on the diaphragm 24 to counteract the force of the spring 42. Thus. the gas pressure in the chamber 25 supplements the force of the spring 35 so that the valve 3| engages the seat 34 at a predetermined pressure in the chamber 25 to thereby arrest the flow of gas into the latter chamber. By moving the screw 51 into or out of the upper part 22 of the valve casing, the pressure required in the chamber 25 to eii'ect closing of the valve 3| can be regulated as desired.

Gas or carbon dioxide thus maintained in the chamber 25 at a predetermined pressure is conducted from such chamber through a passage 49 formed in the upper casing part 22, and thence through an elbow fitting 59 threaded at 5I into the upper casing. 'I'he flexible conduit 3 previously mentioned is connected to the elbow tting 50 and carries the gas under regulated pressure to the valve 4 which is connected to the fitting F. This fitting has a bottom end 52 which makes suitable connection with a companion fitting on the keg K, a washer 53 of rubber or the like being provided to ellect a fluid-tight joint. The gas flows through a passage 54 in the fitting F and a fluid-tight connection is established between the tap rod and the fitting above the passage 54 by means of a compressible Jam washer 55 of rubber or the like which closely surrounds the tap rod and which may be compressed by means of a, jam nut 56.

As the temperature of the tubes 8 and 9 of the tap rod T changes under the influence of the beverage in the keg or receptacle K in which the lower end of the tap rod is immersed, the spindle 45 is moved into or out of the casing of the regulating valve V because of the dillerential expansion of the tubes 8 and 9. An increase in the temperature of the tap rod forces the spindle 44 upwardly as viewed in Fig. 2, compressing the spring 42 and thereby increasing the pressure holding the valve 3| ofi.' the seat 34, so that an increased gas pressure is required in the chamber 25 to overcome the increased force in the spring 42. Thus an increased gas pressure is receptacle or keg K through the conduit 3 1n communication with the chamber 25 in the regulator valve.

Upon a decrease in the temperature of the tap rod T the spindle 44 is withdrawn slightly from the chamber 25 because of the differential contraction of the tubes 8 and 9, thereby decreasing the force exerted against the stem of the valve 3| by the spring 42. Hence, a decreased gas pressure is required in the spring 42, and gas or carbon dioxide at a lower pressure is supplied to the keg K through the conduit 3.

In utilizing the apparatus shown in Figs. 1 and 2, the fitting F, with the valve 4 closed, is attached to the keg K to be tapped. The tap rod T is then inserted into the keg through the fitting F in the customary manner, the valves or stopcocks 2 and the chamber 25 to overcome valve 4, ir not already so attached, and the valves 4 and 2 opened to provide a flow of gas from the source B through the valve v and into the tapped keg K. Opening valve l in the beverage line or conduit allows gas pressure in the keg K to force beverage upwardly through the inner tube l of the tap rod, through the valve t and the conduit l to the cooling and dispensing apparatus of the system.

Screw l1 is adjusted to establish a force in the spring Il. which, supplemented by the gas pressure in the chamber 2l, balances the force oi the spring 42 and maintains the desired pressure of gas or carbon dioxide over the beverage in the keg K. Upon a changein temperature of the beverage in the tapped keg, the inner and outer pipes l and I of the tap rod T are differentially expanded or contracted to vary the force in the spring 42 and thereby alter the pressure maintained in the upper chamber It of the regulating valve V. Thus the gas pressure'supplied to the tapped keg is automatically adjusted to correspond to the variations in temperature to which the beverage may be subjected. The relative strengths and sizes of the springs 35 and I2 are so 'adjusted or proportioned that the resultant change in the pressure maintained in the chamber Il for any given change in temperature to which the tap rod T is subjected corresponds to the change in balance pressure required to maintain the original carbon dioxide content in the beer for a like or equal change in temperature. While the action o! the thermally responsive tap rod T is elective to automatically vary the pressure maintained on the beverage in accordance with the temperature variations over a normal operating range, the limits of the pressure range can be manually altered by means of the screw 51. Movement oi this screw to compress the spring 3l lowers the corresponding pressure maintained on the beverage over the normal temperature range, while movement of the screw to decrease the force in the spring 3l raises the pressure maintained on the beverage for each temperature of the latter. Thus the device may be manually adjusted to alter the relationship between the temperature and the pressure of the beverage for the normal temperature range over which the automatic control is operative.

In Figs. 3 through 6 a modification of the invention is illustrated in which a metal tap rod T oi conventional construction extends into the receptacle or keg K through the fitting F and is immersed in the beverage within the keg or receptacle. This tap rod is provided with a valve 50 to which a conduit il may be attached for conducting beverage to the cooling and dispensing apparatus of the system in accordance with conventional practice.

4(Tias or carbon dioxide under pressure is conducted from a suitable high pressure source, such as tank S shown in Fig. l, to a pressure regulating valve V' th h conduit il provided with a shutoil valve O2 and from the valve V' is conducted to the valve 4 oi the ntting F through a suitable exible conduit 03 which corresponds to the nexible conduit 3 previously described.

The valve V' is mounted on a suitable standard such as a bracket I4, which may be secured to a wall oi the room in which the keg or receptacle K is kept. 'Ihe diaphragm and the gas or air controlling valve of the valve V' are simllar to the corresponding parts of the valve V previously described and, accordingly, are indicated bythe same numerals of reference. These specinc parts of the apparatus are, of course. conventional and the present invention is particularly directed to the method of and the apfor controlling the operation of the pressure regulating valve. In the embodiment of the invention shown in Figs. 3 through 6 the casing portion 2i previously described is replaced by casing or housing Il. the latter also having the vent Il previously mentioned. The bolt 4I is forced against the stem of the valve Il to unseat the latter by means of a relatively strong helical coil spring .s which bears against the pressure or retainer plate 4l carried by the diaphragm 24. The spring Cl is disposed in a cylindrical spring chamber 1I formed in the housing Il and bears against a circular disc-like retainer member 1i which is slidable in the chamber 10. Fins or ribs 12, formed on the inside of the walls of the chamber 1I axially oi the latter, engage in notches (not shown) in the edges of the member 1I to prevent rotation of the latter. Mounted for rotation in an elongated journal 1l formed in the casing il is a spindle 14 having a threaded end 1l extending axially into the spring chamber 1I. An integral collar 16 on the spindle 14 bears against one end of the journal 1l and the disc 1i which supports the spring 68 is threaded onto the end 1l of the spindle so that rotation of the spindle in one direction moves the disc 1i to the left, as viewed in Fig. 5, to compress the spring while rotation of the spindle in a reverse direction moves the disc 1| to the right and decreases the force exerted by the spring 6l against the diaphragm 2s.

A gear wheel 11 is keyed on a reduced diameter portion 1l of the spindle 14 and is disposed against the other .end of the journal 1I in gear chamber 1I formed in the casing or housing I8. 'I'he gear wheel 11 meshes with a worm l0 on a shaft 8l rotatably mounted in a journal l2 formed on the housing 63. A ball ls disposed in the closed end of the journal I2 serves as a thrust bearing for the shaft Il. Externally of the housing the shaft Il, secured against endwise movement by a ilanged bushing or thrust bearing BI, receives a large gear I4 which is meshed with a small gear l5 mounted on shaft Iii of a reversible electric motor l1. Preferably the motor l1, which may be of the universal type, is secured as by screws Il to the housing or casing $8 of the valve V. When the motor l1 is energized for rotation in one direction, a drive is established through the gear train l4-li and the worm and gear -11 that rotates the spindle 14 to move the disc 1I to the left to increase the pressure of the spring 88 against the diaphragm 24, Energization of the motor I1 in a reverse direction rotates the spindle 14, through the gear trains described, in a reverse direction to move the disc 1i to the right and decrease the pressure of the spring 69 against the diaphragm 24.

The control of the energization of the motor l1 in forward and reverse directions is effected by means of contacts 9| and l2 adjustably mounted in opposed or confronting relation to one another on an insulating member Il carried by an arm $4 loosely mounted at one end for limited rotational movement on a shaft journaled in the housing or casing Il. The opposite end o'f the arm 04 is formed with an arcuate rack si. the center of curvature of which is at the rotational axis of the shaft Il. This rack meshes wlth small gear 91 of a compound gear mounted on a spindle 98 supported in the chamber 19 by means of a bracket 99 secured to the inside of the casing wall. A large gear of the compound gear, mounted on the shalt 98 and secured to the small gear 91 for rotation with the latter, meshes with a pinion |0| formed on the reduced diameter extreme end portion of the spindle 14. By this arrangement rotation of the spindle 14 is transmitted to the pivoted arm 94 through the reduction gearing |`0091 so that limited pivotal movement is imparted to the arm 94, slightly raising or lowering the block 93 carrying the contacts 9| and 92 (as viewed in Fig. 4) depending upon whether the motor 81 is rotating the spindle 14 to increasev or decrease the force against the diaphragm 24.

Externally of the housing or casing 68 the shaft 95 has secured thereon a walking beam |03. End |04 of the walking beam engages a retainer or bearing member on one end of a helical coil compression spring |06. The other end of the spring bears against the end of a screw |01 threaded through a web |08 formed on the housing '68, The screw is provided with a knurled wheel |09 for adjustment to vary the compression in the spring |0|.k

End ||0 of the walking beam bears against one end of a metallic bellows supported by a web ||2 of the housing 68. An externally threaded extension ||3 attached to the bellows extends through the web ||2 and receives a nut ||4. As shown in Fig. 4, the axis of the bellows parallels the axis of the compression spring |06 so that expansion of the bellows pivots the walking beam |03 and the shaft 95 against the force of the spring |06 in a clockwise direction, while contraction of the bellows results in a pivotal movement of the walking beam |03 and shaft 95 in a counterclockwise direction under the influence of the springV |05.

Mounted on the shaft 95 and secured against relative rotation as by a key ||5 is an arm IIB formed of non-conducting or insulating material, such as Bakelite or hard rubber. A spring metal extension ||1 carried by the arm ||6 is provided with a double contact |9 disposed between the contacts 9| and 92 of the insulating member 93. Normally, the contact ||8 is spaced from each of the contacts 9| and 92 when the arms 94 and 95 are in alignment or neutral position as illustrated in the gures. As previously mentioned, the arm 94 carrying the insulating member 93 is rotatable on the shaft 95, while the arm ||6 carrying the contact 8 rotates or pivots with the shaft 95. Accordingly, the contact ||8 may be brought into engagement with either the contact 9| or the contact 92, depending upon the relative pivotal positions of the arms 94 and ||8 to establish an electrical connection between the respective contacts.

A pair of opposed or reversed field windings are provided in the motor 81 and are indicated at ||9 and |20 of the wiring diagram, Fig. 6. For controlling the direction of rotation of the shaft 85 of the motor, the iield winding |9 is connected to contact 9| while the field winding |20 is connected to the contact 92. A suitable source of electric current is connected by wires 2| and |22 through a switch |23 to the contact ||1 and armature winding |24 of the motor. The field windings |I9 and |20 and the armature winding |24 of the motor are connected together as indicated at |25. While the field coils ||9 and |20 have been shown for simplicity connected directly to the power source through the contacts H1 and 9| and 92, respectively, itis obvious that a relay of conventional form might be used in order to lower the.4 current through the contacts and thereby reduce burning and deterioration of the latter. The motor 81 can be energized for operation in av forward direction by establishing an electrical connection between the contact Ill and the contact 9|, while an electrical connection between the contact ||1 and the contact 9| energizes the motor for operation in a reverse direction;

The bellows is lled with a suitable thermoresponsive fluid, a number of which are now well known, and are commercially used in thermostats and other heat responsive devices. A conductor or tube |28 is connected to the bellows through the extension I3 and extends to a double walled tubular sleeve or bulb |29 in insulating material |30 and disposed in a casing |3| supported by the bracket 54. The casing 13| is formed with top and bottom end openings aligned with the sleeve |29 so that the tap rod can be passed through the casing and circumferentially embraced by the sleeve |29, the latter slidingly engaging the tap rod. The thermal responsive fluid within the bellows is continuous through the conductor |28 and nlls chamber |32 of the double walled sleeve |29. In this manner the thermal responsive iluid is subjected to the temperature of beverage drawn through the tap rod T and because of the heat conductivity of the tap rod is also subjected to the temperature of beverage Within the keg K. Desirably, an insulating sleeve or jacket |33 may be provided for the portion of the tap rod extending between the casing |3| of the thermostatic element and the fitting F attached to the keg K. Thus, heat absorption from the atmosphere by the tap rod T' between the thermostatic bulb or sleeve |29 and the beverage in the keg K is minimized and the response of the expansible uid in the bulb or sleeve |29 more closely follows the temperature condition of the beverage in the keg.

Upon an increase in temperature of beverage flowing or drawn through the tap rod T or in the keg K, the thermal responsive fluid in the double walled sleeve or bulb |29 is heated because of the metallic contact between the tap rod and the sleeve. The heating of the thermal responsive uid increases the pressure of the same, and this increased pressure is transmitted through the conductor tube |28 to the bellows causing the latter to expand. This expansion of the bellows resulting from an increase in temperature of the beverage. pivots the shaft in a clockwise direction, as viewed in Fig. 4, acting through the walking beam |03 and against the force of the spring |06. This movement of the shaft 95 shifts the arm ||6 relative to the arm 94 so that the contact 8 engages the contact 9| and establishes an electrical connection therebetween. When the switch |23 is closed, the motor 81 is thus energized through the field coil winding 9 to rotate the shaft 89 in a forward direction, which, through the gearing previously mentioned, rotates the spindle 14 in a clockwise direction as viewed in Fig. 4,'thereby compressing the spring 69. The increased force in the spring 69 moves the diaphragm 24 against the pressure of the gas in the chamber 25 to raise the valve 3| off the seat 34, thereby admitting gas or carbon dioxide from the source to flow into the chamber 25 of the regulator valve and thence into the keg K, so as to provide an increased gas or carbon dioxide pressure in the keg. The energization of the motor ll continues to increase the force in the spring t! until the rotation of the spindle Il acting through the double gear 1 -llt and the rack It moves the arm Il to shift the contact Il away from the contact Ill. When the motor l1 is thus de-energized, the force in the spring il has been increased to maintain a predetermined pressure in the keg orreceptacle K, which corresponds to the increased temperature and as determined by the thermal responsive huid in the sleeve or bulb |29.

In the event that the temperature in the receptacle or keg K falls, the temperature of the tap rod T is likewise lowered either through the drawing of beverage trom the keg through the tap rod or by heat conductivity from the beverage stored in the keg. The lowering-oi' the tap rod temperature as determined by the thermal responsive nuid in the sleeve or bulb |29 decreases the pressure of such fluid. resulting in the contraction of the bellows Ill by the force in the spring ill acting on the walking beam |03 to pivot the latter and the shaft 95 in a counterclockwise direction as viewed in Fig. 4. In this manner the contact lll engages the contact 92 to establish electrical connection therebetween and to energize the motor l1 through the neld coil i for reverse operation. The reverse operation o! the motor drives the spindle 14 through the gearing connections previously described to rotate in a counterclockwise direction in Fig. 4, thereby allowing the spring 69 to expand. The lessened force in this spring decreases the pressure maintained in the chamber 25 of the regulator valve and the keg K, as is well known. Reverse operation of the the spur gear Ill'actlng through the double gear "--ill and the rack Il moves the arm $4 counterclockwise relative to the arm lil to separate the contacts ill and t2. When the motor is thus stopped the force in the spring 8l is maintained constant to retain the newly established pressure in the receptacle or keg K until the motor is again energized in either a forward or a reverse direction as demanded by the state of the thermal responsive iluid in the bulb or sleeve |29 influenced by a change in the beverage temperature.

For each setting of the valve V' there is a predetermined pressure range over which the control apparatus is automatically operative to vary the pressure maintained on the beverage in response to temperature changes of the beverage over a normal temperature range. the screw |01 the normal compression force in the spring I" can be manually adjusted to change the limits of such pressure range. Increasing the compression of the spring lowers the limits of the range of pressure over which the control is operative, while decreasing the spring compression raises the limits oi.' such pressure range. Accordingly, the present invention provides not only an automatic control for goveming the pressure on the beverage in response to temperature changes but also a manual control whereby the corresponding pressures maintained for all temperatures over a normal operating range can be regulated.

By the present invention an improved method of storing a gas charged beverage is provided wherein the beverage in a closed container has a gas pressure maintained thereon and such pressure is automatically increased by the introduction oi additional gas into the container in remotor l1 continues until4 By rotating sponse to an increase in temperature o! the stored beverage. By this improved method the pressure of the supply gas is varied in response to temperature changes of the beverage and a pressure is assured which is suiicient at all times to retain the desired quantity of carbon dioxide gas in solution in the beverage.

In its preferred embodiments the present invention contemplates apparatus which includes a pressure regulating valve governed in response to the temperature of the beverage so that the established pressure maintained on the beverage is proportional to the temperature of the latter.

The principles of the present invention may be utilized in various ways, numerous modifications and alterations being contemplated, substitution of parts and changes in construction being resorted to as desired, it being understoad that' the embodiments shown in the drawings and described above are given merely for purposes of explanation and illustration without intending to limit the scope of the claims to the specific details disclosed.

What we claim is:

1. Beverage dispensing apparatus comprising a storage receptacle for the beverage, a multiple metallic tap rod extending into the receptacle and having one end immersed in the beverage for withdrawing the same as desired, a pressure regulating valve and means connecting the same to the receptacle for supplying gas under variable pressure to the latter, and means connecting the valve to different parts of the tap rod to govern the valve in response to relative expansion and contraction of said parts of the rod.

2. Beverage dispensing apparatus comprising a storage receptacle for the beverage. a multiple part metallic tap rod extending into the receptacle and having one end immersed in the beverage for withdrawing the same as desired, a pressure regulating valve mounted on the tap rod and having a gas connection with the receptacle ior supplying gas under variable pressure to the latter, and means governing the valve to vary the pressure of the supplied gas in response to relative expansion and contraction of different parts of the rod.

3. Beverage dispensing apparatus comprising a storage receptacle for the beverage, a tap rod extending into the receptacle and having inner and outer parts formed of materials having different thermal expansion, a pressure regulating valve for supplying gas under variable pressure to the receptacle, and separate means connecting the valve to the inner and outer parts of the tap rod to govern the valve in response to different expansion and contraction of the tap rod parts.

4. Beverage dispensing apparatus comprising a storage receptacle for the beverage, a tap rod extending into the receptacle and having inner and outer parts formed of materials having different thermal expanslon, a pressure regulating valve for supplying gas under variable pressure to the receptacle, said valve having a casing supported on the outer rod part'and a diaphragm governing the pressure of supplied gas, and means connecting the inner rod part to the diaphragm to control said gas pressurein response to different expansion and contraction of the inner and the outer parts of the tap rod.

5. Equipment for storing beverage charged with gas comprising a closed container for retaining the beverage under pressure, a metallic heat conducting tap rod extending into the container and immersed in the beverage, means for supplying gas to the container including an adjustable pressure regulating valve, and means having connection with the valve and with the tap rod and operative in response to temperature changes of the tap rod to control the valve and Vary the pressure at which gas is admitted to the container whereby the pressure of the gas is regulated in accordance with temperature changes of beverages retained in static condition, said last named means including a tube disposed withln and supported by the tap rod and extending to the lower portion of the tap rod.

6. Equipment for storing beverage charged with gas comprising a closed container for re taining the beverage under pressure, a metallic heat conducting tap rod extending into the container and immersed in the beverage. means for supplying gas to the container including an adjustable pressure regulating valve having a diaphragm, means having connection with the valve and with the tap rod and operative in response totemperature changes of the tap -rod to control the valve and vary the pressure at which gas is admitted to the container, said last named means including a tube disposed within and supported by the tap rod and extending to the lower portion of the tap rod, said connection of the control means to the valve including a spring arranged to bear against one side of the valve diaphragm, and a manually adjustable spring arranged to bear against the other side of the diaphragm for altering the relationship between the temperature of the tap rod and the pressure of the gas admitted to the container.

7. In beverage dispensing apparatus comprising a storage receptacle for holding a mass of beverage and a regulating valve for controlling gas supplied under variable pressure to the receptacle, a tubular tap rod extending into the receptacle, an velement extending longitudinally through the rod and so disposed as normally to be immersed in the mass of beverage in the container and in direct heat exchanging relation thereto, and an operative connection between said element and the valve for governing the latter.

8. Beverage dispensing apparatus comprising a storage receptacle for the beverage, a tap rod extending into the receptacle and having inner and outer parts formed of materials having different thermal expansion, a pressure regulating valve for supplying gas under variable pressure to the receptacle, said valve having a casing supported on the outer rod part, and means so connecting the inner rod part to the valve as to control the pressure of gas supplied in response to different expansion and contraction of the inner and outer parts of the tap rod.

WALLACE R. KROMER.

CERTIFICATE OF CORRECTION n Patent No. 2,520,969. June 1, 19M.

WALLACE R. KROMER, ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 63 SGC- ond column, line 27, claim l, before the word "metalliclv insert --part; and that the said Letters Patent `:mould be read with this correction therein that the same may conform to the record of the case in the Patent Office..

Signed and sealed this 12th day of October, A. D. 1914.5.

Henry Van Arsdale, (Seal) Acting commissioner cf Patents. 

